The site's operator, utility SSE, has decided to close the site despite being awarded a two-year extension to operate in January 2018.

Hunterston is testing a Siemens Gamesa 6MW offshore wind turbine and the 7MW Mistubishi SeaAngel machine, which was developed prior to the manufacturer's joint venture with Vestas.

SSE said no jobs would be lost from the site, and the decision to decommission Hunterston follows the completion of testing programmes from the two resident turbines.

"Testing of the Mitsubishi turbine is scheduled to end in summer 2018, following this, the decommissioning process is set to commence in late summer with the expectation to have this work completed by winter 2018.

"Plans for the decommissioning of the Siemens turbine will be communicated over the coming months," SSE said in a statement.

According to the SSE website, the test facility briefly stopped operating on 13 October 2017, after its licence expired.

SSE said it had tried to extend its licence earlier in the year but the decision by the local councul was delayed.

On 9 January 2018, the utility received a two-year consent to operate. The turbines were switched back on from 14 March.

SSE said the site had also made £250,000 (€284,000) in grants to local community projects during its operation.